java课设设备管理系统代码

好的，针对你的问题，我可以为你提供一个简单的设备管理系统的代码示例，供你参考。

这个系统主要包含三个模块：设备管理、设备借还、设备报废。其中，设备管理模块包括设备的增加、删除、修改和查询，设备借还模块包括设备的借出和归还，设备报废模块包括设备的报废操作。具体实现如下：

import java.sql.*;
import java.util.Scanner;

public class DeviceManagementSystem {
    private static Connection conn;

    public static void main(String[] args) {
        try {
            // 连接数据库
            connectDatabase();

            // 显示菜单
            showMenu();

            // 关闭数据库连接
            closeDatabase();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    private static void connectDatabase() throws SQLException {
        // 加载 JDBC 驱动
        Class.forName("com.mysql.jdbc.Driver");
        // 创建数据库连接
        conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/device_db", "root", "123456");
    }

    private static void closeDatabase() throws SQLException {
        if (conn != null) {
            conn.close();
        }
    }

    private static void showMenu() throws SQLException {
        Scanner scanner = new Scanner(System.in);

        while (true) {
            System.out.println("请选择操作：");
            System.out.println("1. 设备管理");
            System.out.println("2. 设备借还");
            System.out.println("3. 设备报废");
            System.out.println("0. 退出");

            int choice = scanner.nextInt();
            if (choice == 0) {
                break;
            }

            switch (choice) {
                case 1:
                    deviceManagement(scanner);
                    break;
                case 2:
                    deviceBorrowAndReturn(scanner);
                    break;
                case 3:
                    deviceScrap(scanner);
                    break;
                default:
                    System.out.println("无效的选择，请重新输入！");
                    break;
            }
        }
    }

    private static void deviceManagement(Scanner scanner) throws SQLException {
        while (true) {
            System.out.println("请选择设备管理操作：");
            System.out.println("1. 设备查询");
            System.out.println("2. 设备添加");
            System.out.println("3. 设备修改");
            System.out.println("4. 设备删除");
            System.out.println("0. 返回");

            int choice = scanner.nextInt();
            if (choice == 0) {
                break;
            }

            switch (choice) {
                case 1:
                    queryDevices();
                    break;
                case 2:
                    addDevice(scanner);
                    break;
                case 3:
                    updateDevice(scanner);
                    break;
                case 4:
                    deleteDevice(scanner);
                    break;
                default:
                    System.out.println("无效的选择，请重新输入！");
                    break;
            }
        }
    }

    private static void queryDevices() throws SQLException {
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM device");
        while (rs.next()) {
            System.out.println(rs.getInt("id") + "\t" + rs.getString("name") + "\t" + rs.getString("description") + "\t" + rs.getInt("count"));
        }
        rs.close();
        stmt.close();
    }

    private static void addDevice(Scanner scanner) throws SQLException {
        System.out.println("请输入设备名称：");
        String name = scanner.next();
        System.out.println("请输入设备描述：");
        String description = scanner.next();
        System.out.println("请输入设备数量：");
        int count = scanner.nextInt();

        PreparedStatement pstmt = conn.prepareStatement("INSERT INTO device(name, description, count) VALUES (?, ?, ?)");
        pstmt.setString(1, name);
        pstmt.setString(2, description);
        pstmt.setInt(3, count);
        pstmt.executeUpdate();
        pstmt.close();
    }

    private static void updateDevice(Scanner scanner) throws SQLException {
        System.out.println("请输入设备 ID：");
        int id = scanner.nextInt();

        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM device WHERE id = " + id);
        if (rs.next()) {
            System.out.println("请输入设备名称（原名称：" + rs.getString("name") + "）：");
            String name = scanner.next();
            System.out.println("请输入设备描述（原描述：" + rs.getString("description") + "）：");
            String description = scanner.next();
            System.out.println("请输入设备数量（原数量：" + rs.getInt("count") + "）：");
            int count = scanner.nextInt();

            PreparedStatement pstmt = conn.prepareStatement("UPDATE device SET name = ?, description = ?, count = ? WHERE id = ?");
            pstmt.setString(1, name);
            pstmt.setString(2, description);
            pstmt.setInt(3, count);
            pstmt.setInt(4, id);
            pstmt.executeUpdate();
            pstmt.close();

            System.out.println("设备修改成功！");
        } else {
            System.out.println("设备不存在！");
        }

        rs.close();
        stmt.close();
    }

    private static void deleteDevice(Scanner scanner) throws SQLException {
        System.out.println("请输入设备 ID：");
        int id = scanner.nextInt();

        PreparedStatement pstmt = conn.prepareStatement("DELETE FROM device WHERE id = ?");
        pstmt.setInt(1, id);
        int n = pstmt.executeUpdate();
        pstmt.close();

        if (n > 0) {
            System.out.println("设备删除成功！");
        } else {
            System.out.println("设备不存在！");
        }
    }

    private static void deviceBorrowAndReturn(Scanner scanner) throws SQLException {
        while (true) {
            System.out.println("请选择设备借还操作：");
            System.out.println("1. 设备借出");
            System.out.println("2. 设备归还");
            System.out.println("0. 返回");

            int choice = scanner.nextInt();
            if (choice == 0) {
                break;
            }

            switch (choice) {
                case 1:
                    borrowDevice(scanner);
                    break;
                case 2:
                    returnDevice(scanner);
                    break;
                default:
                    System.out.println("无效的选择，请重新输入！");
                    break;
            }
        }
    }

    private static void borrowDevice(Scanner scanner) throws SQLException {
        System.out.println("请输入设备 ID：");
        int id = scanner.nextInt();

        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM device WHERE id = " + id);
        if (rs.next()) {
            int count = rs.getInt("count");
            if (count > 0) {
                PreparedStatement pstmt = conn.prepareStatement("INSERT INTO device_borrow(device_id, borrow_time) VALUES (?, NOW())");
                pstmt.setInt(1, id);
                pstmt.executeUpdate();
                pstmt.close();

                PreparedStatement pstmt2 = conn.prepareStatement("UPDATE device SET count = count - 1 WHERE id = ?");
                pstmt2.setInt(1, id);
                pstmt2.executeUpdate();
                pstmt2.close();

                System.out.println("设备借出成功！");
            } else {
                System.out.println("设备数量不足，无法借出！");
            }
        } else {
            System.out.println("设备不存在！");
        }

        rs.close();
        stmt.close();
    }

    private static void returnDevice(Scanner scanner) throws SQLException {
        System.out.println("请输入设备 ID：");
        int id = scanner.nextInt();

        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT * FROM device_borrow WHERE device_id = " + id + " AND return_time IS NULL");
        if (rs.next()) {
            PreparedStatement pstmt = conn.prepareStatement("UPDATE device_borrow SET return_time = NOW() WHERE device_id = ?");
            pstmt.setInt(1, id);
            pstmt.executeUpdate();
            pstmt.close();

            PreparedStatement pstmt2 = conn.prepareStatement("UPDATE device SET count = count + 1 WHERE id = ?");
            pstmt2.setInt(1, id);
            pstmt2.executeUpdate();
            pstmt2.close();

            System.out.println("设备归还成功！");
        } else {
            System.out.println("设备未借出，无法归还！");
        }

        rs.close();
        stmt.close();
    }

    private static void deviceScrap(Scanner scanner) throws SQLException {
        System.out.println("请输入设备 ID：");
        int id = scanner.nextInt();

        PreparedStatement pstmt = conn.prepareStatement("DELETE FROM device WHERE id = ?");
        pstmt.setInt(1, id);
        int n = pstmt.executeUpdate();
        pstmt.close();

        if (n > 0) {
            System.out.println("设备报废成功！");
        } else {
            System.out.println("设备不存在！");
        }
    }
}

其中，设备管理模块中的 `queryDevices()` 方法用于查询设备信息，`addDevice()` 方法用于添加设备，`updateDevice()` 方法用于修改设备信息，`deleteDevice()` 方法用于删除设备；设备借还模块中的 `borrowDevice()` 方法用于设备借出操作，`returnDevice()` 方法用于设备归还操作；设备报废模块中的 `deviceScrap()` 方法用于设备报废操作。

这个示例代码仅供参考，具体实现可以根据实际需求进行调整和完善。如果有任何问题，欢迎随时向我提问。